Hitachi Global Storage Technologies Netherlands B.v.

International Business Machines Corporation

Bob Clyde Robinson

Bradley Frederick Baumgartner

Tony Mello

Hong S Seing

Eric Christian O'Brien

Elmer Tyree York

Charles Chung Lee

Andrew Ching Tam

Timothy Carl Strand

Shanlin Duan

Milton Russell Latta

Ullal Vasant Nayak

Yan Liu

Wai Cheung Leung

Steven Harry Voss

Paul Marion Green

Li Tang

Wesley LeRoy Hillman

Hang Fai Ngo

Norman Chu

Carl Robert Mendel

Christopher Ramm

Parul Agrawal

Ka Chi Wong

Erich Chuh

Alma Lujan Ortega-Avery

Andrew John Buhler

Song How Wong-Jessel

Joseph D Perrault

Jose H Garcia

Disclosed is an apparatus and method for dynamic fly height and roll adjustment of a physical asperity sensor (PAS) head. The PAS head is used to test disk asperity heights and mechanical interference (commonly known as glide height and take off height). The PAS may be adjusted through a pivoting device such as a joystick coupled through one or more actuators to the pivoting device by actuator arms. In one embodiment, the actuator is a piezoelectric motor. The PAS head may utilize a detector to indicate the distance of the disk asperity from the PAS head. The method comprises receiving the signal and in response, operating the actuators to adjust the position of the pivoting device to obtain a selected positioning of either the fly height or the roll of the PAS.

Apparatus and method for dynamic fly height adjustment

An in-situ technique for the acoustic emission monitoring of burnish heads while they are cleaning or burnishing magnetic media is described. The burnishing process is monitored and controlled to identify interaction or contact between the head and media due to, for example, burnish head damage, substrate curvature problems, and lube pick-up problems. A piezoelectric sensor is mounted on the burnish arm that holds the burnish heads. When head-disk interaction occurs, stress waves travel through the head to the sensor and an amplified signal is gathered in a tester database as an acoustic emission. Abnormal conditions will trigger an unusual emission that is detected to trigger an alert.

System, method, and apparatus for in-situ acoustic emission monitoring of burnish heads in production during magnetic media cleaning or burnish process

An inspection system using laser light directed at an off-axis parabolic mirror which focuses the beam on the surface being inspected and also serves as the collector for scattered and specular light returned from the surface is described. Specular and scattered light returned from the surface onto the parabolic mirror is divided into appropriate fields and directed onto detectors. In the preferred embodiment a polarized laser is used in conjunction with a polarizing beam splitter and a quarter-wave plate to route the reflected beam to a detector while allowing the original beam to be directed through the same optics. The parabolic mirror and selected additional components may be commonly mounted on a translatable stage which is moved along a radius of the disk when the optical inspection is being performed. Other components of the system such as the laser can remain in a fixed position. The system of the invention can be used to inspect one or both planar surfaces of the disk by providing duplication of selected components appropriately oriented with respect to the second surface.

Surface inspection tool using a parabolic mirror

A method for detecting manufacturing marks on sputtered disks includes rotating the disk three hundred and sixty degrees. As the disk rotates, a sensor is used to detect a quantity of manufacturing marks formed on the outer edge of the disk. If there are less than four manufacturing marks on the edge of the disk, a signal is sent to a warning device to indicate that the disk is defective. The lack of a manufacturing mark is an indication that a gripper used to hold the disk within the sputtering chamber during the sputtering process is bent or otherwise misaligned. As such, a signal is also sent to the warning device to indicate that the grippers within the sputtering chamber must be inspected.

System and method for detecting manufacturing marks on sputtered disks

An apparatus and method for detecting and marking delamination defects on thin film disks are disclosed. The apparatus includes a read/write (R/W) head and a burnishing head mounted on separate arms that access the disk while spinning on the test stand. The controller uses the R/W head to perform an initial magnetic test of selected areas on the disk to establish an initial defect map. The burnish head is then flown over the surface for an extended time to accelerate and open up the latent delamination defects by impacting protruding material. The R/W head is then used to perform a second magnetic test which is compared against the first test to identify the delamination defects which have been developed by the burnishing. The delamination defects are then marked with a magnetic pattern which aids in optically locating the defect during subsequent failure analysis.

Thin film delamination detection for magnetic disks

A disk for a disk drive uses a circular platter having first and second sides and a circumferential edge. The circumferential edge of the disk has four symmetrically spaced apart shadows and a fifth or additional shadow that gives the disk an asymmetrical shadow signature. The fifth shadow is offset relative to the other shadows, which have congruent arcuate lengths and separation. The fifth shadow has an arcuate length that is about half as long as those of the other shadows, and is closely spaced adjacent to one of the other shadows. The asymmetric shadow signatures of the disk is used to precisely determine both the circumferential position of the platters and their planar orientation (i.e., A-side or B-side). For example, when the disk is mounted on a tool spindle and rotated, an optical detector detects the pattern of the shadows and feeds the data to a computer system. The rotational position of the spindle also is relayed to the computer for coordinating the processing of the rotating disk. When the disk is mounted on a different tool, the same shadow signature is used to determine its planar and angular positions.

Disk drive platter using sputter shadows thereon for determining orientation thereof

A system for use in a memory disk test system is disclosed. The system comprises a fixture for holding a disk head and a moveable slide coupled to the fixture. The system includes a non-magnetic motor system engageably coupled to the slide for moving the test fixture. A system and method in accordance with the present invention offers an SDT system which utilizes piezoelectric motors resulting in higher throughput in producing memory disks. The system and method further achieves high performance, is lower cost in implementation, and is more compact than conventional SDT systems. The system and method, by removing time delay, offers the advantage of cycle time reduction over conventional SDT systems.

Non-magnetic system for a memory disk test system

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Hollister, CA, United States of America

Bob Clyde Robinson